Method of making brushes



May 19, 1959 J. VENEKO METHOD OF MAKING BRUSHES Filed Dec. 1. 1953 INVENTOR Leo d, -l/ene/o BY 9 b ATTORNEY United States Patent-O The present invention relates to a method of making brushes and in particular to a method of making those having exceptionally fine bristles as are generally found in sable hair brushes.

These fine bristle brushes are used principally for artistic paintings, drawing, lettering and the like; however, they are also quite advantageous in applying thin,

light Jfinishes to the surfaces of a variety. of articles and products. The disadvantages being, .thatthe sable or other fine bristle brush is too costly, except for very.

special work.

One object of the invention is to provide amethod. of manufacturing material from which a brush having very fine bristles may be economically manufactured.

A further object of the invention is to provide a method whereby the bristles may be progressively exposed when they become worn, ,or it is desired to change the bristles for any reason whatsoever.

Still another object of the invention is to provide a method of making a brush in which the stiffness of the bristle may be controlled within certain limits.

With this and other objects in view, the general principle of the invention is illustrated in the accompanying drawings and described in the detailed description that follows together with the manner and way in which the brush is constructed including its use and advantages.

In the drawings:

Figure 1 is a view in elevation of one edge of a piece of the material from which the brush is made.

Figure 2 .is an edge view in elevation of the brush similar to that shown in Figure 1 showing the brush bristles formed on one end thereof.

Figure 3 is a view in side elevation of the brush il- 7 lustrated in Figure 2.

Figure 4 is an enlarged fragmentary view taken along line 4-4 of Figure 3. t

Figure 5 is a fragmentary view in elevation of another form of brush.

Figure 6 is another fragmentary view in elevation similar to that shown in Figure 5 showing the bristles formed on each end thereof.

Figure 7 is an enlarged sectional view taken along line 7-7 of Figure 5.

Figure 8 is an enlarged sectional view of a modified form of cross-section of brush of the type shown in Figures 5 and 6.

Figure 9 is a view of a form of brush, showing the bristle of conventional length.

Figure 10 is an end view of the same.

Figure 11 is a vertical side view of the brush shown in Figure 9 having a detachable handle secured thereto.

Figure 12 is an end view of the same.

In referring to the drawings, like reference characters are used to designate like and similar parts throughout the several views.

The material from which these brushes are constructed is quite rigid. The material is made by placice ing in almold a plurality of glass fibers under tensionv and parallel. These fibers are normally first covered with a liquid plastic substance and tightly packed into the mold under pressure; The plastic material may be of any type that will burn and support a flame. How

ever, at the present time a polyester resin material is beingv used. This material is referred to generally by numeral 20. The arrangement of the fibers; andplastic 1 is illustrated irrFigui e 4, in which the glass fibers 21 and the plastic binder. 22 is shown in section perpendicular to the longitudinal axis of the brush. The material may take any convenient width or thickness as illustrated in Figures 3, 5 and 6.

The brush may be made as shown in Figures 5 to 8,

that is, in a long pencil-like stick, or it may be made in wide strips as shown in Figures 1 to 3 and 9 to 12. The forms shownqin Figures 5 to 8 are designed principally for more *delicate painting such as that done by artists. These stick brushes may be made with considerable length and in most any desirable cross-sectional form. However, the square form shown in Figure 7 is believed to give the best advantages in manufacturing.

The formsshown in Figures 1 to 3 and 9 to 12 are shown made into wider widths and are provided with slots 24, 25 and 26 into which a detachable handle may be secured. i

to the outer end of the material 20 as shown in Figures,

11 and 12. The :handle consists of a ,gripping portion having two side members 30 and 31 and a clamping portion. For example, the handle is shown made of a stamping, the side portions 30' and 31 being connected at their outer ends at 30" in such a manner as to give them a springing action. The opposite end of the handle is provided on the side 31 with a single row of teeth 32 and on the side 30 with two sets of teeth 33 and 34 for gripping the upper end of the brush material shown at 20 in Figures 9 and 10. In order to clamp the handle to the brush there is provided a screw 36 rotatably mounted in an aperture provided in the recess portion 38 of the side 31 of the handle. The screw is receivable with a similar threaded aperture within the recessed portion 39 of the side 30' of the handle. The screw 36 is provided with an enlarged end 40 to prevent the screw from being completely removed from the threaded aperture when it is unscrewed to attach or remove it from the brush. The depth of the recess 39 and the length of the screw 36 is such that when the handle is tightened into place on the brush the screw end 40 will not extend beyond the outer surfaces of the handle.

While most any kind of groove, may be formed to receive the gripping elements of the hanrdle, the ones shown are designed to be easily formed by the action of three spaced saws, two of which would contact one side of the material and one which would contact the other side of the material while it was traveling along a supporting surface.

The material is preferably formed in a sheet of any convenient width or thickness, after which the sheet is sawed into strips, or sticks of predetermined widths as shown in contrast in Figures 3 and 5. The material is made by coating the individual strands of the glass fibers with a liquid plastic thermosetting, or thermoplastic resin, after which the fibers are placed in a mold under tension and parallelwith each other where they are left until the plastic material has hardened or cured. After the plastic has set the material is removed from the mold and is ready to be made up into various size Patented May 19, 1959 p a flame. Theplastic after it has reached a certain temperature is combustible and will support a flame and continue to burn until extinguished. 'Phelength of the bristles 42 and 42' on the ends of the stick as shown in Figure 6 may be determined by the distance the ends are allowed to burn. The stiffness of the bristles may also be regulated within a limited degree by the amount of carbon left in the bristles. In the burning operation, a considerable amount of carbon is initially left in the bristles, which may be further removed by further burning and brushing the fibers against a fine cloth orv paper material. When the carbon is removed from the glass fibers the brush will be of very fine texture and equal in performanceto a sable bristle brush.

The bristles 44 and 46 as illustrated in Figures 1 to 3 'and9 to 12 are obtained "in exactly the same manner as previously described for the bristles 42 and 42'.

In Figures 2 and '3 the bristles are shown in relatively short form to illustrate that the bristles may be kept short for many types of work, and when they become worn or contaminated they may be sheared off and the material 20 burned back to obtain a fresh group of bristles. This may be carried on from time to time until all of the material 20 is consumed.

In the stick form (Figures 5 and '6), the ends may be pre-formed before they are burned by whittling, filing, sanding or by a suitable machine such as a pencil sharpener or the like to point the stick at any desirable degree for reducing the number of bristles adjacent the end of the brush. The process of burning the stick '4 back from its ends may be continued as long as it is practical to handle it.

It is to be noted that the fiber glass threads will not disintegrate while the plastic binder is burning. The

fibers have excellent strength for their size and are practically indestructible in any type of chemical preparation.

While certain specific forms of the invention have been illustrated and described, it is not intended as a limitation of any kind and therefore the scope of the invention is best defined in the appended claim.

I claim: I t

A method of manufacturing brushes by the steps of coating a plurality of parallel non-combustible glass fibers under tension with a liquid setting combustible plastic material, compressing the two and allowing the plastic to harden, and removing the plastic adjacent the end of the hardened mass by burning to allow the glass fibers to become exposed for a predetermined distance from the end.

References Cited in the file of this patent UNITED STATES PATENTS FOREIGN PATENTS 274,330 Great Britain July 21, 1927 

